package com.itheima.demo07.Integer;

import java.util.ArrayList;

public class Demo02Integer {
    public static void main(String[] args) {
        Integer in = 1;
        in = in + 2;
        System.out.println(in);
        ArrayList<Integer> list = new ArrayList<>();
        list.add(1);
        int a = list.get(0);
        System.out.println(a);
    }
}
